High pressure housing and optical viewing system

Patent metadata

Field	Value
Publication number	US-9810616-B2
Application number	US-201615282594-A
Country	US
Kind code	B2
Filing date	Sep 30, 2016
Priority date	May 30, 2014
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

A system and method for maintaining the face of an optical window at a desired axial position with respect to the face of a high pressure housing, suitable for use in a high pressure optical flow cell for a real time optical particle monitoring system. The window fits within a mounting hole that extends through the pressure housing. The window has a smaller-diameter cylindrical end portion extending to the high pressure side and an opposite larger-diameter cylindrical end portion, with a shoulder between the cylindrical end portions. A threaded retaining member axially compresses a gasket, o-ring, or other compliant sealing member between the shoulder of the optical window and a corresponding shoulder in the mounting hole, creating a static seal and maintaining the high pressure face of the optical window at a desired position over a wide range of temperatures and pressures.

First claim

The invention claimed is:

1. A high pressure housing and optical viewing system for separating a high pressure environment from a low pressure environment and allowing optical analysis of high pressure fluid, the system comprising:
a housing having a first surface configured to face a higher pressure environment, a second opposite surface configured to face a lower pressure environment, and a mounting hole extending through the housing from the first surface to the second opposite surface along a longitudinal axis,
the mounting hole having a first smaller-diameter cylindrical portion with a substantially constant diameter, a second larger-diameter cylindrical portion having a substantially constant diameter larger than the diameter of the first smaller-diameter portion, a first shoulder surface that extends radially outwardly from the first smaller-diameter portion to the second larger-diameter portion of the mounting hole, and an internally-threaded cylindrical portion between the second larger-diameter portion and the second opposite surface of the housing,
an optical window having a first smaller-diameter cylindrical end portion with a substantially constant diameter, a second larger-diameter cylindrical end portion with a substantially constant diameter larger than the diameter of the first end portion, and a radially outwardly extending shoulder surface between the first smaller-diameter cylindrical end portion and the second larger-diameter cylindrical end portion;
the optical window positioned in the mounting hole with the smaller end of the optical window exposed to the higher pressure environment;
a compliant gasket fitting around the first smaller-diameter cylindrical end portion of the optical window and positioned axially between the shoulder portion of the window and the first shoulder surface of the mounting hole; and
an externally-threaded retaining member positioned in the internally-threaded cylindrical portion of the mounting hole, such that tightening the externally-threaded retaining member compresses the gasket against the first shoulder of the mounting hole, creating a static seal and positioning the smaller end of the optical window at a desired axial position with respect to the first surface of the housing.

2. The system according to claim 1 , further comprising:
a spacer positioned in the mounting hole between the optical window and the externally-threaded retaining member, the flat spacer being more compliant than the externally-threaded retaining member.

3. The system according to claim 2 , further comprising:
a washer being positioned in the mounting hole between the window and the spacer,
the washer being thinner than and formed of a more compliant material than the spacer, and the spacer being thinner and formed of a more compliant material than the externally-threaded retaining member,
wherein tightening the externally threaded retaining member compresses the washer and spacer against the window and compresses the gasket against the first shoulder of the mounting hole.

4. The system according to claim 3 , wherein each of the washer, the spacer, and the externally threaded retaining member have a hole extending therethrough, such that light can pass through an optical path through the window and the holes in the retaining member, the spacer, and the washer.

5. The system according to claim 4 , wherein the holes extending through the washer and spacer each have a diameter that is smaller than the diameter of the first end portion of the optical window.

6. The system according to claim 3 , wherein the spacer comprises polyamide-imide.

7. The system according to claim 3 , wherein the washer comprises a plastic formed from a polyethylene terephthalate resin.

8. The system according to claim 1 , wherein the desired position of the smaller end of the window is flush with the first surface of the housing.

9. The system according to claim 1 , wherein the compliant gasket comprises a synthetic rubber and fluoropolymer elastomer.

10. The system according to claim 1 , wherein the compliant gasket comprises at least one of fluorosilicone and fiberglass.

11. The system according to claim 1 , wherein the compliant gasket is an o-ring.

12. The system according to claim 1 , wherein the compliant gasket comprises a metal seal.

13. The system according to claim 12 , wherein the metal seal comprises a c-ring, an e-ring, or a u-ring.

14. The system according to claim 1 , wherein the compliant gasket comprises a braided metal gasket, a graphite gasket, a sheet gaskets, a piston ring, a spring-energized gasket, a ring-type joint gasket.

15. A method of positioning the face of an optical window at a desired position with respect to a high pressure face of a housing, comprising:
providing a housing having a first surface configured to face a higher pressure environment, a second opposite surface configured to face a lower pressure environment, and a mounting hole extending through the housing from the first surface to the second opposite surface along a longitudinal axis,
the mounting hole having a first smaller-diameter cylindrical portion with a substantially constant diameter, a second larger-diameter cylindrical portion having a substantially constant diameter larger than the diameter of the first smaller-diameter portion, a first shoulder surface that extends radially outwardly from the first smaller-diameter portion to the second larger-diameter portion of the mounting hole, and an internally-threaded cylindrical portion between the second larger-diameter portion and the second opposite surface of the housing,
providing an optical window having a first smaller-diameter cylindrical end portion with a substantially constant diameter, a second larger-diameter cylindrical end portion with a substantially constant diameter larger than the diameter of the first end portion, and a radially outwardly extending shoulder surface between the first smaller-diameter cylindrical end portion and the second larger-diameter cylindrical end portion;
positioning the optical window in the mounting hole with the smaller end of the optical window exposed to the higher pressure environment;
positioning a compliant gasket around the first smaller-diameter cylindrical end portion of the optical window axially between the shoulder portion of the window and the first shoulder surface of the mounting hole;
positioning an externally-threaded retaining member in the internally-threaded cylindrical portion of the mounting hole; and
tightening the externally-threaded retaining member to compress the gasket against the first shoulder of the mounting hole, creating a static seal and positioning the smaller end of the optical window at a desired axial position with respect to the first surface of the housing.

Assignees

• Us Navy

Inventors

• Tucker John E
• Howard Paul L
• Reintjes John F

Classifications

• G01N21/0317

  High pressure cuvettes; (G01N21/0332 - G01N21/15 take precedence) · CPC title

• G01N2015/0053

  in liquids, e.g. trouble · CPC title

• G01N21/05

  Flow-through cuvettes (G01N21/09 takes precedence; handling fluid samples G01N1/10) · CPC title

• G01N33/2858

  Metal particles · CPC title

• G01N15/0227 Primary

  using imaging; using holography · CPC title